02-04-2017 05:17 AM
Here's a real easy problem. It could be due to my PC SAS version 9.4 running Windows 7.
I am trying to multiply all the elements of a vector using SAS function PROD, but it is giving me an error "ERROR 68-185: The function PROD is unknown, or cannot be accessed." The vector may include missing values. The idea is very similar to SAS function SUM, which ignores missing values and sums all the values of the vector.
data _null_; a = prod(2, 1, ., 3); put "a equals " a; run;
But then I get the error. If instead of "prod" I write "sum", there is no error.
Is there something wrong with my base SAS? Do other people have the same problem? What am I doing wrong?
02-04-2017 06:45 AM
PROD() was introduced with SAS/IML, much later than the SUM() function that has been in Base SAS as long as I can remember (SAS 6.09).
It seems nobody ever had a real need for such a function in Base.
You might put it up as a ballot idea.
02-05-2017 08:05 AM
There is not a PROD() function in BASE SAS. But if your numbers are positive then you might be able to use GEOMEAN() function instead. Example:
data have ; input a1-a4 ; cards; 2 1 . 3 1 1 1 1 10 10 10 10 ; data want ; set have; array x a1-a4 ; prod1 = 1; do i=1 to dim(x); prod1=prod1*coalesce(x(i),1); end; prod2=geomean(of x(*))**n(of x(*)); put (_all_) (=); run;